Local police release video of an Uber self-driving car hitting a pedestrian.

Police in Tempe, Arizona, have released dash cam footage showing the final seconds before an Uber self-driving vehicle crashed into 49-year-old pedestrian Elaine Herzberg. She died at the hospital shortly afterward.

The accident occurred after dark on Sunday evening. Herzberg was walking with a bicycle across a poorly lit roadway. About 1.4 seconds elapse between the time when Herzberg starts to become visible (initially, only her feet are faintly illuminated) and the video’s final frame.

While Herzberg is visible for less than two seconds in the camera footage, she might have become visible earlier to a human driver, since human eyes are better at picking out details in low-light situations. Also, the Uber vehicle was presumably equipped with lidar and radar—sensors that work just as well in the dark as they do in broad daylight.

Tempe police also released internal dash cam footage showing the car’s driver, Rafaela Vasquez, in the seconds before the crash. Vasquez can be seen looking down toward her lap for almost five seconds before glancing up again. Almost immediately after looking up, she gets a look of horror on her face as she realizes the car is about to hit Herzberg.

We don’t know what caused Vasquez to look down. We also don’t know if she would otherwise have been able to stop—or at least slow—her vehicle in time to save Herzberg’s life.

But the footage is sure to prompt debate about the role of “safety drivers” in autonomous vehicle testing. Sitting behind the wheel of a car that mostly drives itself for hours is a tedious job, so drivers face a constant temptation to look down at a smartphone or other distraction.